青藏高原20种灌木幼苗生物量分配、水分利用效率及叶片δ^(13)C比较  

Comparison on Biomass Allocation and Leaf Water Use Efficiency and δ^(13)C of 20 Shrub Seedlings in Tibetan Plateau

作　　者：邱权[1] 潘昕[1] 李吉跃[1] 王军辉[2] 董蕾[1] 马建伟 杜坤 

机构地区：[1]华南农业大学林学院,广东广州510642 [2]中国林业科学研究院林业研究所国家林业局林木培育重点实验室,北京100091 [3]甘肃省小陇山林业科学研究所,甘肃天水741022

出　　处：《西北林学院学报》2014年第4期8-14,20,共8页Journal of Northwest Forestry University

基　　金：林业公益性行业科研专项(200904033);农业科技成果转化资金项目(2011GB24320010)

摘　　要：以青藏高原地区各地分布的柠条(Caragana korshinskii)等20种灌木树种为试验材料在苗圃培育,通过测定其生物量、根冠比、叶片瞬时净光合速率、蒸腾速率、水分利用效率及碳同位素组成δ13C,对比灌木树种间生物量分配和水分利用效率的差异,并综合评价灌木树种抗旱性。结果表明,灌木树种间各指标均有显著性差异(p<0.05),取值范围分别为根冠比0.11~0.80、叶片蒸腾速率3.24~6.61 mmol·m-2·s-1、水分利用效率1.85~4.43μmol·mmol-1和δ13 C-26.09‰^-30.22‰。植物的抗旱适应机制主要包括叶片旱生形态型、节水型、高根冠比型和高水分利用效率型,不同属植物和同属不同种植物之间抗旱性均有明显差异,其中沙棘属植物总体抗旱性较差。此外,灌木抗旱性与原产地有一定的联系,其中青海地区灌木总体抗旱性优于西藏和甘肃地区。综合分析抗旱性生理指标发现,金露梅、蔷薇、尼泊尔锦鸡儿、三颗针和胡颓子抗旱性能较好,总体上属于低耗水、高生产效率、抗旱性强树种,在干旱地区造林时可以优先考虑。In this study, 20 kinds of shrubs represented by Caragana korshinskii were transplanted in nurs- ery to make a comparison on their differences in biomass allocation and water use efficiency by measuring their biomass yields, root shoot ratio （RSR）, leaf net instantaneous photosynthetic rate （P.）, transpira- tion rate （T.）, water use efficiency （WUE） and carbon isotopic composition （δ13C）. The comprehensive evaluations of drought resistance of the shrubs were conducted. The results showed that RSR, P., Tr, WUE and δ13C of 20 shrubs were significantly different （p〈0.05）. The RSR, leaf Tr, WUE and δ13C var- iedin the range of 0. 11--0. 80, 3. 24--6. 61 mmolH2O·m-2 · s^-1, 1. 85--4. 43 μmol · mmol^- 1, --26.09‰-30.22‰, respectively. On the other hand, different kinds of shrubs had different adapta- tion mechanisms of drought resistance, mainly including leaf blade xerophytic form, water-saving and high RSR and high WUE. Plants among different genera and those within the same genus exhibited obviousdifferences in drought resistance, and the comprehensive drought resistance of plants of Hippophae was relatively poor. In addition, drought resistance of shrubs had a close connection with their collection re- gions. Drought resistance of shrubs collected from Qinghai was superior than that from Gansu and Xizang. In reference to comprehensive analysis results of performance on drought resistance, it was found that Potentilla fruticosa , Rosa multi flora, Caragana sukiensis , Berberis julianae and Elaeagnus pungens had stronger abilities of drought resistance, manifested by their lower water consumptions, higher WUE, stronger drought resistance, so they should be given priority for the afforestation in the arid areas.

关 键 词：根冠比 水分利用效率 碳同位素组成δ13C 灌木 青藏高原 

分 类 号：S718.43[农业科学—林学]